This application seeks to develop a new method to direct the 3-D assembly of biomolecules and synthetic polymers. This will be done by cross-linking molecules in a highly controlled manner using mutiphoton illumination. A wide range of biological molecules will be incorporated in the 3-D structures while maintaining their bioactivity. The investigators claim that their approach provides benefits over current methods including photolithography, microcontact printing and free-form microfabrication. This will be accomplished with higher optical resolution, preservation of biological function, and improved 3-D capability. Feasibility has been demonstrated by fabricating structures with synthetic polymers, proteins, hydrogels, and active enzymes. The proposed work will develop fabrication methods with wide applicability in a number of biological and bioengineering fields. Specific goals are: 1) to fabricate structure for applications in biosensors, gene chips, protein-based micro-machines, micrometer scale-enzyme factories, and biomaterials. 2) To fabricate nano and micro-scale gels for application in biosensors, drug delivery, and tissue engineering. 3) To fabricate dimensionally complex channels and structures for applications to microfluidics. 4) To fabricate composites and biomaterials for tissue engineering.